Left atrial appendage segmentation and quantification in 3d and 4d cardiac ultrasound

Abstract

Systems and methods for real time three-dimensional left atrial appendage (LAA) quantification. Deep learning is used to perform LAA segmentation, tracking and live quantification on critical measurement in 4D ultrasound sequences. The collected information may be used for device selection and anomaly detection to assist early-phase disease finding.

1 . A method for real time three-dimensional left atrial appendage quantification, the method comprising:
 acquiring a real time three-dimensional ultrasound sequence of a patient;   selecting a seed location of the left atrial appendage in a frame of the real time three-dimensional ultrasound sequence;   cropping the frame to a region of interest based on the seed location;   generating a three-dimensional left atrial appendage segmentation from the region of interest;   extracting one or more landmarks from the three-dimensional left atrial appendage segmentation;   slicing the three-dimensional left atrial appendage segmentation into a plurality of two-dimensional slices, wherein the plurality of two-dimensional slices each include a portion of a contour of the left atrial appendage;   tracking the contour of the left atrial appendage in the plurality of two-dimensional slices and the one or more landmarks in the real time three-dimensional ultrasound sequence;   generating a real time three-dimensional left atrial appendage segmentation from the tracked contour; and   quantifying at least one metric from the tracked contour and/or the tracked one or more landmarks.   
     
     
         2 . The method of  claim 1 , wherein selecting the seed location comprises:
 freezing the real time three-dimensional ultrasound sequence; and   clicking, by a user, on the seed location inside the left atrial appendage in a frame of the frozen real time three-dimensional ultrasound sequence;   wherein the real time three-dimensional ultrasound sequence is unfrozen after selecting the seed location.   
     
     
         3 . The method of  claim 1 , wherein cropping comprises:
 calculating an estimated shape and size of the left atrial appendage from a collected dataset of images of left atrial appendages of a plurality of patients; and   centering the region of interest around the seed location based on the estimated shape and size.   
     
     
         4 . The method of  claim 1 , wherein the three-dimensional left atrial appendage segmentation is generated using a machine trained network. 
     
     
         5 . The method of  claim 1 , wherein the one or more landmarks comprises at least one of ostium and neck landmarks that determine diameters of the ostium and neck area of the left atrial appendage. 
     
     
         6 . The method of  claim 1 , wherein the contour and the one or more landmarks are tracked in real time using respective neural networks trained using a cycle-consistency loss. 
     
     
         7 . The method of  claim 1 , wherein the at least one metric provides a diameter of the left atrial appendage across time. 
     
     
         8 . The method of  claim 7 , wherein the diameter of the left atrial appendage is used to determine and select properties of a device in a left atrial appendage closure procedure that matches characteristics of the patient's left atrial appendage. 
     
     
         9 . The method of  claim 1 , wherein the real time three-dimensional ultrasound sequence is provided by an ultrasound system configured for Intracardiac Echocardiography. 
     
     
         10 . A system for real time three-dimensional left atrial appendage segmentation, the system comprising:
 an ultrasound imaging system configured to acquire a 4D ultrasound sequence of patient; and   a processor configured to select a seed location of the left atrial appendage in a frame of the 4D ultrasound sequence, crop the frame to a region of interest based on the seed location, generate a three-dimensional left atrial appendage segmentation from the region of interest, extract one or more landmarks from the three-dimensional left atrial appendage segmentation, slice the three-dimensional left atrial appendage segmentation into a plurality of two-dimensional slices, wherein the plurality of two-dimensional slices each include a portion of a contour of the left atrial appendage, track the contour in the plurality of two-dimensional slices over time and the one or more landmarks in the 4D ultrasound sequence, and quantify at least one metric from the tracked contour and/or the tracked one or more landmarks.   
     
     
         11 . The system of  claim 10 , wherein cropping comprises:
 calculating an estimated shape and size of the left atrial appendage from a collected dataset of images of left atrial appendages of a plurality of patients; and   centering the region of interest around the seed location based on the estimated shape and size.   
     
     
         12 . The system of  claim 10 , wherein the processor is configured to generate the three-dimensional left atrial appendage segmentation using a machine trained network. 
     
     
         13 . The system of  claim 10 , wherein the one or more landmarks comprises at least one of ostium and neck landmarks that determine diameters of the ostium and neck area of the left atrial appendage. 
     
     
         14 . The system of  claim 10 , wherein the processor is configured to track the contour and the one or more landmarks in real time using respective neural networks trained using a cycle-consistency loss. 
     
     
         15 . The system of  claim 10 , wherein the at least one metric provides a diameter of the left atrial appendage across time. 
     
     
         16 . The system of  claim 15 , wherein the diameter of the left atrial appendage is used to determine and select properties of a device in a left atrial appendage closure procedure that matches characteristics of the patient's left atrial appendage. 
     
     
         17 . The system of  claim 10 , wherein the ultrasound imaging system is configured for Intracardiac Echocardiography. 
     
     
         18 . A system comprising:
 an ultrasound imaging system configured to acquire a 4D ultrasound sequence of patient;   a display configured to display the 4D ultrasound sequence;   an input device configured to identify a seed location for a left atrial appendage in a frame of the 4D ultrasound sequence; and   a processor configured to crop the frame to a region of interest based on the seed location, generate a three-dimensional left atrial appendage segmentation from the region of interest, slice the three-dimensional left atrial appendage segmentation into a plurality of two-dimensional slices, wherein the plurality of two-dimensional slices each include a portion of a contour of the left atrial appendage, track the contour in the plurality of two-dimensional slices in real time, and generate a real time three-dimensional left atrial appendage segmentation from the tracked contour.   
     
     
         19 . The system of  claim 18 , wherein the processor is further configured to identify one or more landmarks in the three-dimensional left atrial appendage segmentation and track the one or more landmarks over time in the 4D ultrasound sequence. 
     
     
         20 . The system of  claim 19 , wherein the processor is further configured to quantify at least one metric from the real time three-dimensional left atrial appendage segmentation and/or the tracked one or more landmarks.